The molecular recognition theory proposes that complementary nucleotide sequences encode peptides that interact as a result of a genetically- determined inversion of their respective hydropathic profiles. Furthermore, the theory predicts that in certain instances the binding sites of interacting proteins will be encoded by complementary nucleotide sequences. The overall objective of this proposal is to test this prediction within the immunologic network. Specifically, we will study idiotypic and anti-idiotypic monoclonal antibodies and T cell clones against encephalitogenic peptides from myelin basic protein. The hypothesis to be tested is whether: (a) the binding sites of idiotypic and anti-idiotypic monoclonal antibodies or the T cell receptor or T clones to peptides of myelin basic protein contain the complementary primary sequences as projected by this theory; (b) there is sequence homology between the epitopes of myelin basic protein and one or more of the complementarity determining regions of the monoclonal anti-idiotypic antibody recognizing the idiotype bearing monoclonal antibody to the myelin basic protein epitope. If the theory proves applicable to the immune system, such knowledge could be applied to understanding autoimmune inflammatory demyelination such as in multiple sclerosis and experimental allergic encephalomyelitis.